Problem: Add. ${6} + {12} =$
Explanation: First, let's jump ${6}$ on the number line. $+6$ $0$ $2$ $4$ $6$ $8$ $10$ $12$ $14$ $16$ $18$ $20$ Next, let's jump ${12}$ on the number line. $+6$ $+12$ $0$ $2$ $4$ $6$ $8$ $10$ $12$ $14$ $16$ $18$ $20$ The jumps end at the number ${18}$. $+6$ $+12$ $\boxed{18}$ $0$ $2$ $4$ $6$ $8$ $10$ $12$ $14$ $16$ $20$ ${6} + {12} = {18}$